C# loop and keypress break loop

Question

My code consists of something like this:

{
    var comeback = Cursor.Position;
    code goes here
    code goes here
    code goes here
    code goes here
    code goes here
    code goes here
    Cursor.Position = restart;
}

Now, I wish to have this continuously looped until such time as I invoke a keypress to stop.

What I cannot do i write the code for this loop, or is there a different way I should be going about this.

Thanks in advance

I don't understand. Are you asking how to write an infinite loop in C#? Try `for(;;)` — Cody Gray - on strike, Apr 25 '11 at 13:58
Yes I wish this to be a infinite loop, which will have a keypress event to stop — Kyle, Apr 25 '11 at 13:59
Now that we know this is a WinForms application, you **do not** want an infinite loop on your UI thread. That will lock up your application, and prevent it from either responding to user input or updating anything displayed on the screen. — Cody Gray - on strike, Apr 25 '11 at 14:05
Infinite loops in a WinForm application is a horrible idea :$ — Security Hound, Apr 25 '11 at 14:09

score 9 · Answer 1 · answered Apr 25 '11 at 14:01

9

while(!Console.KeyAvailable)
{
    //do work
}

answered Apr 25 '11 at 14:01

spender

117,338
33
229
351

3

Late info ("And it is a winform") invalidates this answer. – spender Apr 25 '11 at 14:02
2

still, since this is a nice way to do it for consoleapplications you get a +1 from me (other people looking for "keypress loop" might be interested in your answer) – default Apr 25 '11 at 14:13

default · Answer 2 · 2011-04-25T14:23:15.333

since OP thanked me for the first answer, I'll keep that as reference below..

consider having a background thread that does the loop. Then add a key listener in your project (if you have visual studio, open up the properties tab and check out events) by double clicking the KeyPressed event. You'll get something like this:

    private bool keyPressed;

    public MyClass() {
        keyPressed = false;
        Thread thread = new Thread(myLoop);
        thread.Start();
    }

    private void myLoop() {
        while (!keyPressed) {
            // do work
        }
    }

    private void MyClass_KeyPress(object sender, KeyPressEventArgs e) {
        keyPressed = true;
    }
}

Consider having a thread that listen for a keypress and then set a flag in your program that you check in your loop.

for instance Untested

bool keyPressed = false;
...    
void KeyPressed(){
    Console.ReadKey();
    keyPressed = true;
}
...
Thread t = new Thread(KeyPressed);
t.Start();
...
while (!keyPressed){
    // your loop goes here
    // or you can check the value of keyPressed while you're in your loop
    if (keyPressed){
        break;
    }
    ...
}

@Javed. yeah.. I noticed the added comment.. I am thinking about how to edit my answer.. — default, Apr 25 '11 at 14:11

score -2 · Answer 3 · answered Apr 25 '11 at 13:59

-2

HAVE A BOOLEAN VARIABLE.

like bool flag = true; while(flag) { your code; }

when the key is pressed, change the flag to false.

answered Apr 25 '11 at 13:59

Dipti Mehta

537
3
13

How do you propose to check the key press?? – MoonKnight Feb 07 '12 at 09:57

C# loop and keypress break loop

3 Answers3